Submitted by Timothy Bowles on
Our lab is currently investigating innovative soil management strategies tailored to urban agricultural systems and aimed at reducing costs of production while enhancing climate resilience of agroecosystems. In partnership with the Berkeley Food Institute, we have joined a coalition of soil scientists, ecologists, city planners, and cooperative extension specialists to develop practices that will address concerns over soil health and soil contamination in the city.
One part of this work is a two-year experiment at Berkeley’s 0.25 ha research field, the Oxford Tract. We are comparing a novel no-till method (based on intensive compost use on the soil surface) with tillage methods typically used by urban and peri-urban farmers. We hypothesize that this practice will increase soil organic matter (SOM) and crop water use efficiency. Second, we are examining how cover crops designed to break through subsoil compaction (e.g. forage radish) can lead to increased cash crop rooting depth and deep water extraction, potentially also enhancing drought resilience.
With a focus on both soil ecology and the efficiency of crop production, we will track key metrics of soil health over the course of the two-year experiment, including total soil organic carbon (C), total soil organic nitrogen (N), and an indicator of labile soil organic matter, permanganate oxidizable C. Measurements could also include microbial biomass C, microbial biomass N, and other key indicators of microbiota such as extracellular enzyme activities or genomic analysis. The experiment will also track other soil physical and chemical factors such as as inorganic N (ammonium, nitrate), soil water retention, and clay silicate composition, as indicators of the mineral and water holding capacity of the soil. Ultimately, these will be compared with measured crop yields, labor requirements, and input costs (e.g. compost, cover crop seeds, and water) to evaluate the economic and environmental benefits of these agroecological practices.
All this work points towards an understanding of "soil health," the dynamic properties of soil that support the production of food and fiber while providing key ecosystem services such as water filtration, carbon storage, and contaminant buffering. We are also deeply concerned with how the health of the soil supports healthy communities. This is where we engage with "food justice," delivering free produce through our robust network of partner organizations to people in need. How can creating vibrant agroecosystems address food insecurity and the resilience of impacted urban communities?
The student who joins this project will have the opportunity to participate at multiple scales simultaneously. The student will be trained in soil sampling techniques, soil processing, and chemical analysis of soil samples for measurement of soil organic matter fractions. Since this field experiment will be for a minimum of two years, development of independent research questions related to soil health, water use efficiency, agroecology, soil-pest interactions, etc., will be encouraged. The student will also learn basics of experimental design and help maintain field research plots (e.g planting and irrigation). Students will learn how to analyze basic chemical and biological functioning of soil systems, analyze resulting data, and report back to the group on key findings.
- Have a background in ecology, environmental science, chemistry, biology, or related fields
- Maintain a 3.0 GPA or higher
- Understand basic soil ecology, and its intersection with biochemistry, mineralogy, microbiology, etc.
- Be passionate/have experience in farming or gardening
- Preferably have research experience in a laboratory/bench chemistry environment
- Work independently and be able to summarize and communicate findings clearly